She'elot UTeshuvot Onlinehttp://www.daat.ac.il/daat/chinuch/index.html
Thousands of brief Hebrew responsa from Israeli rabbis, since 2001. You can
browse by category (e.g., refuah, machshavah, nashim) or by rabbi (e.g., Rav Rozen
of Zomet, Rav Yuval Sherlo). If you sign up, you can ask questions as well.

Cypess -- The Electronic Parsha Warehouse http://eparsha.com/
The best link page for parashah on the web. Hundred of links divided by topics
(e.g., peshat commentaries, academic articles, divrei torah from yeshivot and
institutions, non-Orthodox torah, etc.) Includes search engines for divrei torah at
Shamash, and for the Mail-Jewish and Avodah archives

Guide Sheets for Reading Nevi'im and Ketuvim: A System for Study and Review, by Seth (Avi) Kadishhttp://www.lookstein.org/resources
Hebrew guides to reading each of the books of Nach. (They're in pdf form, so download Acrobat Reader.)

Da'at (the English page)http://www.daat.ac.il/daat/english/index.html
Dozens of articles, especially medical ethics in halakhah. Includes education
articles from Ten Da'at and halakhah articles from the Journal of Halacha and
Contemporary Society (RJJ).

Jewish Torah Audio http://www.613.org/
Provides over 600 hours of Jewish audio and video. You must first download the
Real Audio software.

Jewish Law -- Articles http://www.jlaw.com/Articles
Dozens of halakhah articles, especially from the Journal of Halacha and
Contemporary Society (RJJ), focus on how Jewish law perceives American law.

Dafyomi Advancement Forum: The Internet Center for the Study of Dafyomihttp://www.dafyomi.co.il/
You can subscribe to email classes, or use the archives. It covers most pages of
the Talmud with a variety of classes, including Insights, Background, Point by
Point Summary, and Charts and Graphics.